Connecting device for use with stranded metal cables



J. w AsTLEY Nov. 1, 1932.

CONNECTING DEVICE FOR USE `WITH STRANDED METAL CABLES Fild June 23, 1931 Patented Nov. 1', 1932 JOHN WILLIAM ASTLEY,OF PRESCOT, ENG-LAND, ASSIGNR T0 BRITISH INSU'LA'IIEEI) PATENT* OFFICE. f

. CABLES LIMITED, OF PRESCOT, LANGASHIRE, ENGLAND, BRI'lISI-IV COMPANY .ooivivriciiiie DEV-ion noia Usii WITH s'rRANnEiJ METAL CABLES .Application led June23, 1931, Serial 546,329, and in' Great Britain .Tuly 5, 1930.

rIhis invention'relates to devices for making connection between a length of cable 'and some other member A which may be another length of cable or maybe a solid bar or eye or p. 5 other body. "It deals particularly with "the case where thecable consists of two concentric groups of wires or of an louter group of wires and of Ya single central wire. Where these two groups are of different metals for in- .io stance a steel centre group and an aluminium outer group) it has been recognizedas'desirable that the method ofV connection Ashould provide a certain amount of independence between the connections of the two groups.

My improved arrangement is of a type in which this condition'isrealized by the use of clamping actions obtained by therrelative displacementof inner and router cones between each pair of which thewires of a single group arefengaged.

I make use of an louter -conical member for the outer group ofv wires of considerably greater length than the inner conical member for that group and Imount the outer conical memberl for the inner group withinfthe extended end of that outer cone. In an arrangement of this kind itis of course necessary to make the clamping l action for the Youter group of wires effective before putting the clamping cones for the inner group of wires into position and it is accordingly necessary to force the inner cone for the outer grouptightly against the inner surface of thatrgroup of wires. Owing tothe extension .w of the outermost cone at the outside andthe projection of the inner group of wiresat the centre it is necessary to use an annular member which should surroundthe inner group of wires land' can be forced against the end of 450 the innerl cone for the outer group of wires and drive this cone into position. y

I-Iitherto it has been the practice touse a vshort length of pipe or other annular punch to transmit the blows of a hammer to the end 455 of the inner conefor the outer group of wires.

.load over the Atwo vof the arrows. y K Over the ends A and B of the two composite strands are threaded two aluminium By the present invention I avoid the use of this annular tool and simplify the forcing in of the cone and make more vaccurate'the adjustment of the clamping grip exerted byit.

I provide the outer cone for the inner group of wires with an external threadworkf ingin a correspondingly threaded portion of the large endlof the .outer cone for the outer group of. wires and I usethe first of these two `threaded members to press against. the

largerend of the inner vcone for the outer f the outer cone for that group to exert the necessary'initial clamping effect. After this 'has been done the inner cone for the' inner group of wires is driven into positiongyfor in'stance .by a hammer, striking on'its outer en By this method of adjustment ofthe clampingit isf'ound possible to provide the correct initialv relationship for the outer group of wires for such a material as aluminium to kpermit the further movementto take .placeof this'outer group of wireswhen the tension loadcomes on the cable, which movement I have found to be practically essential in order toobtain a proper distribution pf the'tens'ile groups Yof wires whenthe inner one is of steel.

An example of the application of the invention is illustratedv in detail by the accompanying drawing which' shows an assembled connector Joining two sectionsjof asteel-cored aluminium stranded conductor.

'Y Figure l is a longitudinalsection through the centr-e of thejoint in the plane of theconductor, and

Figure 2 is a transverse section on the line i X-X in Figure l and viewed in the direction conical members 1 and 2 which are of similar internal construction but differ in resp-ect to their external characteristics for reasons described below. rlibe various components of the connector which are assembled within the conical members 1 and 2 are similar for each half of the joint, consequently a detailed description of the side A of the joint will also cover the side B.

The end of the composite stranded conductor is trimmed so that the steel core which constitutes the inner group of wires 8 project beyond the aluminium strands constituting the outer group of wires 41. A small aluminium conical member 5 is threaded over the inner group of wires 3 so that the outer group of wires 1 are spread out against the inner surface of the outer cone 1. The outer cone 1 is provided with an internally threaded portion 6 which is intended to receive the threaded portion of an outer steel conical member 7 for the inner group of wires 3. An extension 8 to the outer steel cone 7 makes contact with the larger end of the inner aluminium cone 5 so that the action of screwing the former into the outer aluminium cone 1 causes the extension 8 to press the inner aluminium cone 5 against the inside of the outer group of wires 11, thereby clamping them against the inside of the outer cone 1.

A hexagonal projection 9 upon the screwed portion of the outer steel cone 7 for theinner group of wires facilitates the screwing of this cone into position within the outer aluminium cone 1; the latter is made hexagonal in shape 10, or as in the case of the conical member 2, is provided with flats 11, as a means for engagement during screwing up.

To clamp the inner group of wires 3 against the conical inner surface of the steel cone 7, a small split steel cone 12 is driven into place by means of hammer blows.` The barrel of this cone is provided with teeth or serrations which grip the central wire as the split sections close forced into the conical cavity formed by the steel cone 7.

In its final position the outer steel cone 7 abuts against a shoulder or seat 18 on the inside of the outer aluminium cone 1, which takes the tensile load and prevents it being borne by the threaded portion. This construction is particularly important in a case such as the example described where the outer cone is constructed of aluminium.

The diameter of the interior threaded portion of the other aluminium cone 1 is sulficiently greater than the diameter of the adjacent inner conical surface to allow the use of a reamer or similar tool to produce an accurate conical surface without damage to the screw threads.

The twoy adjacent ends A and B of the stranded conductors being fitted with the clamping arrangements as described, have to due to the cone being l Y length of cable, comprising an outer group be drawn together by a sleeve member, of which there are several well known types. The figures illustrate a sleeve 14 provided with an inner shoulder 15 which bearsV against a shoulder 16 on the outer conical member 2; the inside of the other end of the sleeve 14E has a screw-thread which engages with a screw-thread 17 on the outer conical member 1. The action of screwing the sleeve 14 into place draws the twohalves of the joint together until the inner steel cones meet as shown in Figure 1. TheV sleeve 141 is made hexagonal in section as shown in Figure 2 to facilitate the action of screwing it into place. A lock nut 18 is screwed on to the outer conical member 2 aga-inst the back of the sleeve 1A to prevent any tendency for the sleeve to unscrew due to vibration.

Another well known type of sleeve is provided with right and left hand screw-threaded portions which engage with corresponding threaded portions on the outermost conical members 1 and 2, or their equivalents, the two sections being drawn together by rotation of the sleeve.

To prevent deterioration of the exposed metal within the joint, arrangements are made which allow the cavities to be filled with a suitable compound. Ascrew plug 19 permits the compound to be poured into the joint, and longitudinal holes 2G are provided in the outer conical member 7 for the 'inner group of wires which permit the compound to flow into the cavities whichraccommodate the severed ends of the outer group of wires.

lVhere it is desired tojoin a length of cable to a solid bar or eye. or such like body then only one half of the joint as Vdescribed above is necessary. The solid member must be adapted to `receive a sleeve member by means of which the joint may be closed in afmanf ner similar to that described above.

What I claim as my Vinvention and desire to secure by Letters Patent is Y A device for connecting an end of a of wires and acore consisting of an' inner group of wires or a single central wire, to another but possibly similar member, said device comprising meansV for engaging the said cable end, means for engaging the other member and a sleeve coupling these two engaging means together, the first of said engaging means comprising an inner clamping cone and an outer clamping cone for each group of wires, the inner clamping cone for the outer group of wires being loroo cated within the smaller end of the outer clamping cone for that group, the inner cone for the inner group being located at least in part, within the outer cone for that group, which latter cone is located within the larger end of the outer clamping cone of the outer group of wires so that it can press upon the inner clamping cone for the outer group of vWires when the cable end is engaged, the outer clamping cone for the outer group of Wires havin at its larger end an internal screw threa and the outer cone for the inner group of Wires having a corresponding eX- ternal thread Working therein and also having an axial projection engageable by a tool whereby it may be screwed intovthe outer cone for the outer group and thereby be caused to prese against and tighten up the inner cone for the outer group of Wires when the cable end is engaged. In testimony whereof I affix my signature. Y

JOHN WILLIAM ASTLEY. 

